Method of making distensible bag catheters and the like



Sept. 28, 1943. G. l.. WINDER METHOD OF MAKING DISTENSIBLE BAG CATHETERS AND THE LIKE Original Filed Aug. 9, 1939 2 Sheets-Sheet 1 b.. {Iliff/lilik if 5555;@ L-l/ndsza.

Sept. 28, 1943. G. 1 WINDER METHOD OF MAKING DISTENSIBLE'BAG CATHETERS AND THE LIKE Original Filed Aug. 9, 1959 2 Sheets-Sheet 2 27 EH'DJL- /ws/w. W////////////////////////%vwvwwwww Patented Sept. 28, 1943 METHD F MAKING DISTENSIBLE BAG CATHETERS AND THE LIKE George L. Winder, Cuyahoga Falls, Ohio, assignor, -by mesne assignments, to American Anode, Inc., Akron, Ohio, acorporation of Delaware Original applications September 11.v 1937, Serial No. 163,422, and August 9, 1939, Serial No. 289,242. Divided and this application November 12, 1942, Serial No. 465,310

This invention relates to rubber surgical accessories and particularly to drainage catheters provided with distensible bagsof the type especially designed for controlling hemorrhage following trans-urethral re-section of the prostate gland and for similar purposes, as well as the so-called self-retaining distensible bag catheters, and to methods of manufacturing such accessories.

This application is a division of each of my co-pending applications, Serial No. 163,422, filed September 11, 1937, and Serial No. 289,242, filed August 9, 1939.

The invention has for .its major objects the provision of more satisfactory, more eflicient, and more dependable distensible bag catheters, and the provision of economy and efllciency in the manufacture of such rubber articles of compli-` cated structures. More particularly, the invention aims to provide a catheter provided with a bag which shall be more easily distensible than the bags of similar products now available; to provide a bag which shall distend uniformly in a desired shape; to provide a bag which shall distend to the required shape with minimum stretching of the rubber and consequent reduc- Fig. 4 is an elevation, partially broken away for clarity of illustration, illustrating further steps in the process; j Fig. 5 is a section taken on line 5-5 of Fig. 4; Fig. 6 is .a sectional elevation illustrating a further step in the process and showingl the assembly of Fig. 4 immersed in a liquid rubber Acomposition receiving a coating of rubber;

Fig'. 7 is ya fragmentary elevation, partially broken away, showing a portion of the product of the step illustrated in Fig. 6, after further operations have been performed upon it;

tion in danger of bursting or otherwise failing in use to provide a distensible bag catheter so constructed as to eliminate the possibility of the drainage tube collapsing under pressure from the distended bag; to provide a catheter with a separately formed and attached bag without the usual abrupt edges at the juncture of the bag with the wall of the catheter proper; to provide novel procedure for manufacturing distensible bag catheters; to provide novel procedure for attaching the distensible bag to the body of the catheter proper; to provide novel procedure for incorporating collapse-resisting reinforcements in distensible bag catheters; and to provide other novel features in construction and manufacture of distensible bag catheters.

The manner in which these and other objects of the invention are achieved will be apparent from the following description of preferred embodiments of the invention as illustrated in the accompanying drawings of which:

Fig. l is a sectional elevation illustrating the initial step in the process'of manufacturing a distensible bag catheter according to one embodiment of the present invention and showing two deposition forms immersed in a liquid rubber composition receiving coating deposits of rubber;

Fig. 2 is a section taken on line 2-2 of Fig. 1;

Fig. 3 is a section taken on line 3-3 of Fig. 1;

Fig. 8 is a sectional elevation illustrating the step of forming the distensible bag;

Fig. 9 is a fragmentary sectional elevation illustrating the step of affixing the bag to the catheter;

Fig. `10 is a sectional elevation illustrating a further step in the process and showing the assembled catheter and bag immersed in a liquid rubber composition for receiving a, finishing coating of rubber;

Fig. 11 is an elevation, partially sectioned for clarity of illustration, showing the distensible bag catheter made by the procedure illustrated in Figs. 1 to 10;

Fig. 12 is a fragmentary elevation, partially sectioned and broken away, illustrating a slight modification in the manner of axing the distensible bag to the catheter proper as illustrated in Fig. 9;

Fig. 13 is a fragmentary sectional elevation j illustrating a modified procedure in which the distensible vbag is formed in situ;

Fig. 14 is a sectional elevation illustrating an early step in a modified procedure for forming a reinforced distensible bag catheter;

Fig. 15 is a section taken on line I5+I5 of Fig. 14;

Fig. 16 is a fragmentary elevation illustrating a further step in the modified procedure and showing reinforcing elements in place on'the product of Fig. 14;

Fig. 17 is a fragmentary sectional elevation showing a portion of the main body of a catheter made by the modified procedure ready for application of the distensible bag;

Fig. 18 is a section taken on line I8-I8 of Fig. 17;

Fig. 19 is a fragmentary elevation showing the finished distensible bag catheter made by the modified procedure illustrated in Figs. 14 to 18.

As the novel features of construction embodied in the present distensible bag catheters may be most readily understoodfrom a consideration of the procedures by which they are made, the invention will be described primarily from the procedural point of view, the structure of the product becoming evident as the description proceeds.

In manufacturing a distensible bag catheter according to one procedure illustrative of my invention, I utilize two deposition forms, a principal or drainage-tube form I0, and an auxiliary or distension-duct form II, made of any suitable material, but preferably of a light-weight, noncorrodible metal such as aluminum. The drainage-tube form I consists of a relatively long rodlike portion I2 corresponding to the desired lumen size, with a gradually tapered head I3 at one end. The distension-duct form I I consists of a straight rod-like element Il of cresentiform cross-section having a length somewhat less than the length of the rod-like portion I2 of the form I0, and having an off-set extension I5 terminating in a gradually tapered head I6 generally like the head I3 of the form III.

In the process, the two forms III and II are immersed to points well up on the tapered heads in a liquid rubber composition I1 contained in a suitable tank I8 (Fig. 1) and coatings of rubber I9a, I9b, each about 0.10" to 0.15" thick are deposited respectively upon the forms I0 and II. The liquid rubber composition I1 may be a solution of rubber in a solvent such as the so-called rubber cements, or a natural or artificial aqueous dispersion of rubber, and the rubber coatings may be produced upon the forms in any desired manner. Preferably, however, the liquid rubber composition I1 should be a concentrated natural rubber latex suitably compounded with the usual vulcanizing and conditioning agents, and the deposition of the rubber coatings from such latex desirably is effected by using a coagulant preliminarily applied to the form as in U. S. Patent No. 1,908,719, and if necessary, also using a pulverulent separating material upon the forms as. in U. S. Patent No. 1,924,214, to facilitate stripping the rubber deposits from the forms.

Next, the two coated forms are assembled and pressed together with the concave portion of the coated crescentiform rod I l of the form II lying along the circular rod I2 of the form III and extending from a point about two or three inches from the tip of the form I0 to a point near the tapered portion I3, with the oil'set extension I5 of the form II projecting outward in the common plane of the assembled forms. Cohesion of the unvulcanized rubber deposits ordinarily will be sufficient to hold the assembled forms in proper relation for subsequent handling, but may be augmented if necessary by rubber cement or by thin rubber bands or the like placed aroimd the assembly at spaced points. 'Ihe assembled coated forms are then immersed again in the liquid rubber composition and an additional coating of rubber is produced upon the assembly to build up a. deposit of rubber merging with the previous deposits to provide an overall coating Isc about 0.30 to 0.40" thick as most clearly shown in Fig. 5. It is also possible to mount the two forms I0 and I I in4 proper spaced relation and dip them in the liquid rubber composition while so mounted, and thereby to form the double-tubed rubber structure with one dipping operation.

For providing collapse-resisting reinforcement in the body of the catheter proper, when required, a piece of ordinary square-woven cotton fabric such as common cheese-cloth" 20, or other fabric, is impregnated with latex or other rubber composition and wrapped about the deposit I 9c at the end of the distension duct form II where the distensible bag is desired, the fabric being held in place by cohesion of the latex on the fabric with the latex rubber of the deposit I9c. A single wrap of the rubberized fabric with the edges abutting provides a smooth structure and ordinarily furnishes adequate reinforcement, although several successive wraps of fabric may in some cases be desirable.

Also at this stage of the process, a tip-reinforcing metal cup 2I may be placed over the tip of the deposit to prevent puncture of the nished catheter by the stylet or sound employed in inserting the catheter through the urethra when it is used.

Thereupon the assembly is again immersed in the liquid rubber composition I1 to receive another coating of rubber which serves to enclose or embed the reinforcing fabric 20 and the metal cup 2| wholly within the rubber wall of the catheter as clearly shown in Fig. 6, the composite merged rubber deposits being designated by the numeral I9d. When the rubber deposit ISd has dried sufciently to permit handling, a small aperture 22 is cut through the rubber I9d and the fabric 20 to expose a short length of the distension-duct form I I at a point near the tip end, and thereby to provide communication into the duct formed in the catheter wall by the form Il. Also, shallow circumferential grooves 23, 23 are pressed or cut in the rubber I9d at spaced positions on either side of the opening 22 to receive the ends of the distensible bag flanges as will more clearly appear later.

The distensible bag itself is prepared separately by depositing a coating of rubber 25 about 0.10" thick from the liquid rubber composition I1 upon a suitable deposition form (Fig. 8) consisting of a bulbous portion 26 shaped to produce the bulbous bag 25a, and having opposed stems 21, 21 designed to form tubular flanges 25h, 25h upon the bag of a diameter adapted to iit snugly about the rubber body ISd of the catheter, the flanges of course being trimmed after the bag deposit 25 is stripped from the bag deposition form. The bulbous form 26 preferably has an unsymmetrical prolate spheroidal configuration as illustrated to produce a bag broadly termed pear-shaped" for fitting the prostatic fossa closely. Also, the form 26 preferably is provided with series of intersecting longitudinal and circumferential surface grooves 28, 28 which produce in the Wall of the distensible bag corresponding intersecting longitudinal and circumferential ribs or molded corrugations 29, 29 (depending upon the thickness of rubber deposited and whether or not the groove is lled with deposited rubber), which serve to insure uniform distension of the bag upon injection of fluid.

Upon completion of the distensible bag, the prepared catheter body I9d (Fig. 7) is inserted through the bag and the ends of the bag flanges 25h, 25h, are brought into alignment with and turned down into the grooves 23, 23, the tension in the slightly stretched rubber flanges assisting materially in this operation, and the entire assembly is again immersed in the liquid rubber composition I1 (Fig. 10) to deposit a thin illm of rubber over the assembly which merges with the previous rubber deposits to form a unitary rubber deposit I9e and also serves to secure the bag firmly to the body of the catheter, and especially to produce a smooth exterior surface free of abrupt attacco subjected to the usual washing, drying, and vul-v canizing treatments. the deposition forms I and are stripped from within the deposits, drainage eyelets are cut in appropriate positions, and

the ends of the outlet tubes are trimmed, ali according to usual procedure requiring no detailed explanation.

The procedure described for attaching the distensible bag to the body of the catheter Amay ad vantageously be modied by making the grooves 23, 23 wide enough to receive the entire respective flanges 25h, 25h, as illustrated in Fig. 12, thereby further contributing to a smooth exterior surface. f

The finished catheter made by the process described, as illustrated in Fig. l1, is seen to consist of a principal drainage tube 30 having drainage eyelets 3|, 3| at the distal end, a distensible bag 25 surrounding the main body of the catheter adjacent the eyelets, with an auxiliary or distenwhereby the bag may be distended by injecting fluid through the duct. The distensible bag is pre-formed with a bulbous pear shape so that minimum stretching of the rubber bag and minimum distending pressure Will be necessary for fitting the bag closely to the prostatic fossa, uneven distension of the bag being minimized by the ribs or molded corrugations 29, 29. Although the bag is formed separately and affixed to the body of the catheter, a smooth exterior surface is nevertheless presented, thereby overcoming a serious defect in the usual type of assembled bag catheter. Other advantages of the product are apparent.

For causing the catheter, or a desired local por- In a modified procedure, the distensible bagmay be formed in situ by treating the local circumferentialarea of the catheter body where the bag is desired with a substance ladapted to prevent adhesion in that area of a subsequently applied deposit of rubber. For example, a local circumferential area or surface band of the rubber body of the catheter including the opening 22, may be treated with a separating material such as a suspension of soapstone in alcohol, or with a chemical such as a bromine, chlorine, or sulfur chloride, in a suitable solvent, to prevent adhesion of the subsequently applied rubber deposit, and then immersed in a liquid rubber composition to produce the final coating of rubber forming the distensible bag in situ over the treated area. When a collapse-resisting fabric reinforcement is embodied in the catheter, it has been found advantageous not to embed the fabric in the body of the catheter as heretofore described,

ber and to utilize the fabric for retaining pulverulent separating material upon the catheter body. Referring particularly to Fig. 13, the catheter body designated |9f is produced in the manner described upon the deposition forms I 0 and The rubberized fabric reinforcement 2|! is then wrapped about the body |9f at the tip end of the form |I, and an opening 22 is made through the fabric and rubber to expose a short length of the form and provide communication into the distension duct. The fabric 20 is then preferably treated as by brushing thereon an appropriate quantity of a syrupy coating composition containing 60 grams of soapstone suspended in one liter of acetone or alcohol containing 500 grams of a latex coagulant such as calcium nitrate or zinc nitrate, thereby producing, after the alcohol or acetone has evaporated, a separating layer 33 uponthefabric andin the opening 22. The assembly is then dipped in latex and a final coating of rubber is produced thereon adhering to the body I9f except over the treated fabric where a circumferential layer of rubber 34 is produced forming an integral bag which may be distended by injecting fluid through the distension duct, the pulverulent separating material in the opening 22 of course being easily displaced by the distending fluid.

.In a further modified embodiment of the invention (Figs. 14 to 19), a coil wire reinforcement is utilized which necessitates a circular 1 cross-section in the main body of the catheter.

along the form from a point about two or three inches from the tip end to a point near the enlarged head, together with a rod-like auxiliary but to wrap the rubberized fabric reinforcement 20 about the body of the catheter after it is complete except for the bag-forming deposit of rubor distension-duct form 42 having a circular cross-section adapted to t in the groove in the principal form. The two forms are coated with rubber in the manner described, the coated auxiliary form is placed in the groove ci' the coated principal form, and the assembly is coated with rubber (Fig. 14) to build up an integral deposit of rubber 43 about half the thickness desired in the wall of the catheter. Next, a coil wire reinforcing element 44, is placed over the tubular portion of the deposit 43, and a U shaped tip-reinforcing Wire element 45 is placed over the tip o f the deposit with the legs of the U extending to and being mechanically engaged with the coil reinforcing element 44 (Fig. 16). The coil reinforcing element 44 may be formed of about 0.007

inch gauge stainless steel wire and should have a low pitch of about 20 coils to the inch. The coil element preferably extends from a point between the position (in the finished catheter) of the drainage eyelets and the distal end of the bag to a point adjacent the convergence of the drainage tube and the distension duct but may be restricted to a portion only of the length of the catheter, as for example merely the length covered by the distensible bag.

When the wire reinforcing elements 44 and 45 have been properly positioned, the assembly is immersed in the liquid rubber composition and a deposit of rubber of sufllcient'thickness to cover the wire is produced thereon to embed the wire completely within the wall of the catheter. Small openings 46, 46 then are cut in the catheter wall to provide communication into the distension duct near the tip end of the distension duct form 42, and a distensible bag 41 is affixed to the catheter over the openings 46, in the manner described. To complete the catheter, the forms 4|,

l2 are removed, drainage eyelets I8 are cut adl1acent the tip, the open ends of the drainage tube and the distension duct are trimmed, and the rubbexis washed, dried, and vulcanized as before.

As will be noted, the distensible bag 41 is formed with a pear-shaped conguration for fitting the prostatic fossa, and that it also is formed with longitudinal flutes or folds I9 to facilitate easy and uniform distention of the bag, while maintaining minimum size of the undistended bag for easy passage through the urethra. The coil wire reinforcing element 44 eilectively prevents collapse of the drainage tube under collapsing pressure, and even when the tube is bent sharply, while the U shaped tip reinforcement 45 imparts rigidity to the tip and facilitates passage through the urethra. Other advantages of the embodiment of Fig. l1 of course are inherent in the modied embodiment of Fig. 19.

It therefore appears that the invention as described attains to a high degree the objects hereinabove set forth.

The various specific features of construction and procedure described in connection with the several different embodiments of the invention of course may be interchanged and combined in many obvious ways, and the invention is by no means restricted to the particular combinations of features illustrated and described. Also, numerous modifications and variations in details of operative procedure and materials herein described may be made without departing from the spirit and scope of the invention as deilned by the appended claims.

I claim:

l. A method of making a surgical appliance or similar article. which comprises producing a rubber tube, mapping a local circumferential region lof the tube with a fibrous collapse-resisting reinforcement, treating at least a portion of the iibrous element with material adapted to prevent adhesion of a liquid rubber composition, coating the assembly with a liquid rubber composition whereby a distensible bag is produced about the gube, and providing means for distending the 2. A method of making a surgical appliance or similar article, which comprises producing a rub ber tube, wrapping a circumferential region of the tube with a fibrous collapse-resisting reinforcement, treating at least a portion of the flbrous element with pulverulent separating material adapted to prevent adhesion of a liquid rubber composition, coating the assembly with a liquid rubber composition to form a distensible bag about the tube and over the treated portion of the reinforcing element, and providing means for distending the bag.

3. A method of making a surgical appliance or similar article, which comprises producing a rubber tube, wrapping a textile fabric reinforcing element about the tube in a local zone thereof. treating the textile fabric with a liquid suspension of a pulverulent separating material adapted to prevent adhesion of a liquid rubber composition, and coating the assembly with a liquid rubber composition to form a distensible bag about the tube and over the treated textile fabric.

GEORGE L. WDTDER. 

